Not everyone who struggles in life would rather not live. I think it's quite arrogant to contemplate whether living is worth it for another human being.
I find it arrogant to force a human being to life, especially at this time. I question everyday the fact that somebody else decided for me that life is somewhat worth living.
Even so, that person will not be you. Even if they will go through exactly the same things you've been through they may not have the same experience. You cannot know if it was worth it for them.
I think it's fine if people don't have kids, I just find the reasoning "what if they suffer, etc" a cop-out. You cannot know that beforehand and even if they suffer, they may still find meaning in life.
Last several replies you gave are such high quality. I hate it when people overintellectualize such obvious things like having a kid. I would have flipped out at the other poster, but you stuck in there and gave some really good points. Awesome.
So is joy, happiness and pleasure. I feel sorry for you if your life is only filled with regret and misery. For most people there are ways out of misery but it all starts with the realization that it's not a necessity. When you're depressed it's difficult to imagine ever being able to feel anything else again but knowing that it is possible can put you on the right track.
Maybe your need to pass judgement on my character based on two posts should tell you something about yourself. It really takes an inflated ego to, as a non-parent, talk about responsibility with a parent. Paraphrasing: "Responsibility as a parent is heavy as a mountain, deciding not to have children is light as a feather".